Translated from Latin to
English, "Ad Hominem" means "against the man" or
"against the person."
An Ad Hominem is a
general category of fallacies in which a claim or argument is rejected on the
basis of some irrelevant fact about the author of or the person presenting the
claim or argument. Typically, this fallacy involves two steps. First, an attack
against the character of person making the claim, her circumstances, or her
actions is made (or the character, circumstances, or actions of the person
reporting the claim). Second, this attack is taken to be evidence against the
claim or argument the person in question is making (or presenting). This type
of "argument" has the following form:
1. Person A makes claim X.
2. Person B makes an attack on person A.
3. Therefore A's claim is false.
The reason why an Ad
Hominem (of any kind) is a fallacy is that the character, circumstances, or
actions of a person do not (in most cases) have a bearing on the truth or
falsity of the claim being made (or the quality of the argument being made).
1. Bill: "I believe that abortion is morally wrong."
Dave: "Of course you would say that, you're a priest."
Bill: "What about the arguments I gave to support my position?"
Dave: "Those don't count. Like I said, you're a priest, so you have to say
that abortion is wrong. Further, you are just a lackey to the Pope, so I can't
believe what you say
2. Fallacy: Ad Hominem Tu Quoque
Also Known as: "You Too Fallacy"
This fallacy is
committed when it is concluded that a person's claim is false because 1) it is
inconsistent with something else a person has said or 2) what a person says is
inconsistent with her actions. This type of "argument" has the
following form:
1. Person A makes claim X.
2. Person B asserts that A's actions or past claims are inconsistent with
the truth of claim X.
3. Therefore X is false.
The fact that a person
makes inconsistent claims does not make any particular claim he makes false
(although of any pair of inconsistent claims only one can be true - but both
can be false). Also, the fact that a person's claims are not consistent with
his actions might indicate that the person is a hypocrite but this does not
prove his claims are false.
1. Bill: "Smoking is very unhealthy and leads to all sorts of
problems. So take my advice and never start."
Jill: "Well, I certainly don't want to get cancer."
Bill: "I'm going to get a smoke. Want to join me Dave?"
Jill: "Well, I guess smoking can't be that bad. After all, Bill
smokes."
3.
Fallacy: Appeal to Authority
Also Known as: Fallacious Appeal to Authority, Misuse
of Authority, Irrelevant Authority, Questionable Authority, Inappropriate
Authority, Ad Verecundiam
An Appeal to Authority
is a fallacy with the following form:
1. Person A is (claimed to be) an authority on subject S.
2. Person A makes claim C about subject S.
3. Therefore, C is true.
This fallacy is
committed when the person in question is not a legitimate authority on the
subject. More formally, if person A is not qualified to make reliable claims in
subject S, then the argument will be fallacious.
This sort of reasoning
is fallacious when the person in question is not an expert. In such cases the
reasoning is flawed because the fact that an unqualified person makes a claim
does not provide any justification for the claim. The claim could be true, but
the fact that an unqualified person made the claim does not provide any
rational reason to accept the claim as true.
When a person falls prey
to this fallacy, they are accepting a claim as true without there being
adequate evidence to do so. More specifically, the person is accepting the
claim because they erroneously believe that the person making the claim is a legitimate
expert and hence that the claim is reasonable to accept. Since people have a
tendency to believe authorities (and there are, in fact, good reasons to accept
some claims made by authorities) this fallacy is a fairly common one.
Since this sort of
reasoning is fallacious only when the person is not a legitimate authority in a
particular context, it is necessary to provide some acceptable standards of
assessment. The following standards are widely accepted:
1. The person has sufficient expertise in the subject matter in question.
Claims made by a person who lacks the
needed degree of expertise to make a reliable claim will, obviously, not be
well supported. In contrast, claims made by a person with the needed degree of
expertise will be supported by the person's reliability in the area.
Determining whether or not a person has
the needed degree of expertise can often be very difficult. In academic fields
(such as philosophy, engineering, history, etc.), the person's formal
education, academic performance, publications, membership in professional
societies, papers presented, awards won and so forth can all be reliable
indicators of expertise. Outside of academic fields, other standards will
apply. For example, having sufficient expertise to make a reliable claim about
how to tie a shoe lace only requires the ability to tie the shoe lace and
impart that information to others. It should be noted that being an expert does
not always require having a university degree. Many people have high degrees of
expertise in sophisticated subjects without having ever attended a university.
Further, it should not be simply assumed that a person with a degree is an
expert.
Of course, what is required to be an
expert is often a matter of great debate. For example, some people have (and
do) claim expertise in certain (even all) areas because of a divine inspiration
or a special gift. The followers of such people accept such credentials as
establishing the person's expertise while others often see these
self-proclaimed experts as deluded or even as charlatans. In other situations,
people debate over what sort of education and experience is needed to be an
expert. Thus, what one person may take to be a fallacious appeal another person
might take to be a well supported line of reasoning. Fortunately, many cases do
not involve such debate.
If a person makes a claim about some
subject outside of his area(s) of expertise, then the person is not an expert
in that context. Hence, the claim in question is not backed by the required
degree of expertise and is not reliable.
It is very important to remember that
because of the vast scope of human knowledge and skill it is simply not
possible for one person to be an expert on everything. Hence, experts will only
be true experts in respect to certain subject areas. In most other areas they
will have little or no expertise. Thus, it is important to determine what
subject area a claim falls under.
It is also very important to note that
expertise in one area does not automatically confer expertise in another. For
example, being an expert physicist does not automatically make a person an
expert on morality or politics. Unfortunately, this is often overlooked or
intentionally ignored. In fact, a great deal of advertising rests on a
violation of this condition. As anyone who watches television knows, it is
extremely common to get famous actors and sports heroes to endorse products
that they are not qualified to assess. For example, a person may be a great
actor, but that does not automatically make him an expert on cars or shaving or
underwear or diets or politics.
If there is a significant amount of
legitimate dispute among the experts within a subject, then it will fallacious
to make an Appeal to Authority using the disputing experts. This is because for
almost any claim being made and "supported" by one expert there will
be a counterclaim that is made and "supported" by another expert. In
such cases an Appeal to Authority would tend to be futile. In such cases, the
dispute has to be settled by consideration of the actual issues under dispute.
Since either side in such a dispute can invoke experts, the dispute cannot be
rationally settled by Appeals to Authority.
There are many fields in which there is a
significant amount of legitimate dispute. Economics is a good example of such a
disputed field. Anyone who is familiar with economics knows that there are many
plausible theories that are incompatible with one another. Because of this, one
expert economist could sincerely claim that the deficit is the key factor while
another equally qualified individual could assert the exact opposite. Another
area where dispute is very common (and well known) is in the area of psychology
and psychiatry. As has been demonstrated in various trials, it is possible to
find one expert that will assert that an individual is insane and not competent
to stand trial and to find another equally qualified expert who will testify,
under oath, that the same individual is both sane and competent to stand trial.
Obviously, one cannot rely on an Appeal to Authority in such a situation
without making a fallacious argument. Such an argument would be fallacious
since the evidence would not warrant accepting the conclusion.
It is important to keep in mind that no
field has complete agreement, so some degree of dispute is acceptable. How much
is acceptable is, of course, a matter of serious debate. It is also important
to keep in mind that even a field with a great deal of internal dispute might
contain areas of significant agreement. In such cases, an Appeal to Authority
could be legitimate.
If an expert is significantly biased then
the claims he makes within his are of bias will be less reliable. Since a
biased expert will not be reliable, an Argument from Authority based on a
biased expert will be fallacious. This is because the evidence will not justify
accepting the claim.
Experts, being people, are vulnerable to
biases and predjudices. If there is evidence that a person is biased in some
manner that would affect the reliability of her claims, then an Argument from Authority
based on that person is likely to be fallacious. Even if the claim is actually
true, the fact that the expert is biased weakens the argument. This is because
there would be reason to believe that the expert might not be making the claim
because he has carefully considered it using his expertise. Rather, there would
be reason to believe that the claim is being made because of the expert's bias
or prejudice.
It is important to remember that no person
is completely objective. At the very least, a person will be favorable towards
her own views (otherwise she would probably not hold them). Because of this,
some degree of bias must be accepted, provided that the bias is not
significant. What counts as a significant degree of bias is open to dispute and
can vary a great deal from case to case. For example, many people would
probably suspect that doctors who were paid by tobacco companies to research
the effects of smoking would be biased while other people might believe (or
claim) that they would be able to remain objective.
Certain areas in which a person may claim
expertise may have no legitimacy or validity as areas of knowledge or study.
Obviously, claims made in such areas will not be very reliable.
What counts as a legitimate area of
expertise is sometimes difficult to determine. However, there are cases which
are fairly clear cut. For example, if a person claimed to be an expert at
something he called "chromabullet therapy" and asserted that firing
painted rifle bullets at a person would cure cancer it would not be very
reasonable to accept his claim based on his "expertise." After all,
his expertise is in an area which is devoid of legitimate content. The general
idea is that to be a legitimate expert a person must have mastery over a real
field or area of knowledge.
As noted above, determining the legitimacy
of a field can often be difficult. In European history, various scientists had
to struggle with the Church and established traditions to establish the
validity of their discliplines. For example, experts on evolution faced an
uphill battle in getting the legitimacy of their area accepted.
A modern example involves psychic
phenomenon. Some people claim that they are certified "master psychics"
and that they are actually experts in the field. Other people contend that
their claims of being certified "master psychics" are simply absurd
since there is no real content to such an area of expertise. If these people
are right, then anyone who accepts the claims of these "master
psychics" as true are victims of a fallacious appeal to authority.
A common variation of the typical Appeal
to Authority fallacy is an Appeal to an Unnamed Authority. This fallacy is also
known as an Appeal to an Unidentified Authority.
This fallacy is committed when a person
asserts that a claim is true because an expert or authority makes the claim and
the person does not actually identify the expert. Since the expert is not named
or identified, there is no way to tell if the person is actually an expert.
Unless the person is identified and has his expertise established, there is no
reason to accept the claim.
This sort of reasoning is not unusual.
Typically, the person making the argument will say things like "I have a
book that says...", or "they say...", or "the experts
say...", or "scientists believe that...", or "I read in the
paper.." or "I saw on TV..." or some similar statement. in such
cases the person is often hoping that the listener(s) will simply accept the
unidentified source as a legitimate authority and believe the claim being made.
If a person accepts the claim simply because they accept the unidentified
source as an expert (without good reason to do so), he has fallen prey to this
fallacy.
As suggested above, not
all Appeals to Authority are fallacious. This is fortunate since people have to
rely on experts. This is because no one person can be an expert on everything
and people do not have the time or ability to investigate every single claim
themselves.
In many cases, Arguments
from Authority will be good arguments. For example, when a person goes to a
skilled doctor and the doctor tells him that he has a cold, then the the
patient has good reason to accept the doctor's conclusion. As another example,
if a person's computer is acting odd and his friend, who is a computer expert,
tells him it is probably his hard drive then he has good reason to believe her.
What distinguishes a
fallacious Appeal to Authority from a good Appeal to Authority is that the
argument meets the six conditions discussed above.
In a good Appeal to
Authority, there is reason to believe the claim because the expert says the
claim is true. This is because a person who is a legitimate expert is more
likely to be right than wrong when making considered claims within her area of
expertise. In a sense, the claim is being accepted because it is reasonable to
believe that the expert has tested the claim and found it to be reliable. So,
if the expert has found it to be reliable, then it is reasonable to accept it
as being true. Thus, the listener is accepting a claim based on the testimony
of the expert.
It should be noted that
even a good Appeal to Authority is not an exceptionally strong argument. After
all, in such cases a claim is being accepted as true simply because a person is
asserting that it is true. The person may be an expert, but her expertise does
not really bear on the truth of the claim. This is because the expertise of a
person does not actually determine whether the claim is true or false. Hence,
arguments that deal directly with evidence relating to the claim itself will
tend to be stronger.
1. Bill and Jane are arguing about the morality of abortion:
Bill: "I believe that abortion is
morally acceptable. After all, a woman should have a right to her own
body."
Jane: "I disagree completely. Dr. Johan Skarn says that abortion is always
morally wrong, regardless of the situation. He has to be right, after all, he
is a respected expert in his field."
Bill: "I've never heard of Dr. Skarn. Who is he?"
Jane: "He's the guy that won the Nobel Prize in physics for his work on
cold fusion."
Bill: "I see. Does he have any expertise in morality or ethics?"
Jane: "I don't know. But he's a world famous expert, so I believe
him."
Kintaro: "I don't see how you can
consider Stalin to be a great leader. He killed millions of his own people, he
crippled the Soviet economy, kept most of the people in fear and laid the
foundations for the violence that is occuring in much of Eastern Europe."
Dave: "Yeah, well you say that. However, I have a book at home that says
that Stalin was acting in the best interest of the people. The millions that
were killed were vicious enemies of the state and they had to be killed to
protect the rest of the peaceful citizens. This book lays it all out, so it has
to be true."
Sasha: "I played the lottery today
and I know I am going to win something."
Siphwe: "What did you do, rig the outcome?"
Sasha: "No,
silly. I called my Super Psychic Buddy at the 1-900-MindPower
number. After consulting his magic Californian Tarot deck, he told me my lucky
numbers."
Siphwe: "And you believed him?"
Sasha: "Certainly, he is a certified Californian Master-Mind Psychic. That
is why I believe what he has to say. I mean, like, who else would know what my
lucky numbers are?"
4.
Fallacy: Appeal to Common Practice
The Appeal to Common
Practice is a fallacy with the following structure:
1. X is a common action.
2. Therefore X is correct/moral/justified/reasonable, etc.
The basic idea behind
the fallacy is that the fact that most people do X is used as
"evidence" to support the action or practice. It is a fallacy because
the mere fact that most people do something does not make it correct, moral,
justified, or reasonable.
An appeal to fair play,
which might seem to be an appeal to common practice, need not be a fallacy. For
example, a woman working in an office might say "the men who do the same
job as me get paid more than I do, so it would be right for me to get paid the
same as them." This would not be a fallacy as long as there was no
relevant difference between her and the men (in terms of ability, experience,
hours worked, etc.). More formally:
1. It is common practice to treat people of type Y in manner X and to treat
people of type Z in a different manner.
2. There is no relevant difference between people of type Y and type Z.
3. Therefore people of type Z should be treated in manner X, too.
This argument rests
heavily on the principle of relevant difference. On this principle two people,
A and B, can only be treated differently if and only if there is a relevant
difference between them. For example, it would be fine for me to give a better
grade to A than B if A did better work than B. However, it would be wrong of me
to give A a better grade than B simply because A has red hair and B has blonde
hair.
There might be some
cases in which the fact that most people accept X as moral entails that X is
moral. For example, one view of morality is that morality is relative to the
practices of a culture, time, person, etc. If what is moral is determined by
what is commonly practiced, then this argument:
1. Most people do X.
2. Therefore X is morally correct.
would not be a fallacy.
This would however entail some odd results. For example, imagine that thereare
only 100 people on earth. 60 of them do not steal or cheat and 40 do. At this
time, stealing and cheating would be wrong. The next day, a natural disaster
kills 30 of the 60 people who do not cheat or steal. Now it is morally correct
to cheat and steal. Thus, it would be possible to change the moral order of the
world to one's view simply by eliminating those who disagree.
1. Director Jones is in charge of running a state waste management program.
When it is found that the program is rife with corruption, Jones says
"This program has its problems, but nothing goes on in this program that
doesn't go on in all state programs."
5.
Fallacy: Appeal to Belief
Appeal to Belief is a
fallacy that has this general pattern:
1. Most people believe that a claim, X, is true.
2. Therefore X is true.
This line of
"reasoning" is fallacious because the fact that many people believe a
claim does not, in general, serve as evidence that the claim is true.
There are, however, some
cases when the fact that many people accept a claim as true is an indication
that it is true. For example, while you are visiting Maine, you are told by
several people that they believe that people older than 16 need to buy a
fishing license in order to fish. Barring reasons to doubt these people, their
statements give you reason to believe that anyone over 16 will need to buy a
fishing license.
There are also cases in
which what people believe actually determines the truth of a claim. For
example, the truth of claims about manners and proper behavior might simply
depend on what people believe to be good manners and proper behavior. Another
example is the case of community standards, which are often taken to be the
standards that most people accept. In some cases, what violates certain
community standards is taken to be obscene. In such cases, for the claim
"x is obscene" to be true is for most people in that community to believe
that x is obscene. In such cases it is still prudent to question the
justification of the individual beliefs.
See also Appeal to Popularity.
1. At one time, most people in Europe believed that the earth was the
center of the solar system (at least most of those who had beliefs about such
things). However, this belief turned out to be false.
6.
Fallacy: Appeal to Emotion
An Appeal to Emotion is
a fallacy with the following structure:
1. Favorable emotions are associated with X.
2. Therefore, X is true.
This fallacy is
committed when someone manipulates peoples' emotions in order to get them to
accept a claim as being true. More formally, this sort of "reasoning"
involves the substitution of various means of producing strong emotions in
place of evidence for a claim. If the favorable emotions associated with X
influence the person to accept X as true because they "feel good about
X," then he has fallen prey to the fallacy.
This sort of
"reasoning" is very common in politics and it serves as the basis for
a large portion of modern advertising. Most political speeches are aimed at
generating feelings in people so that these feelings will get them to vote or
act a certain way. in the case of advertising, the commercials are aimed at
evoking emotions that will influence people to buy certain products. In most
cases, such speeches and commercials are notoriously free of real evidence.
This sort of
"reasoning" is quite evidently fallacious. It is fallacious because
using various tactics to incite emotions in people does not serve as evidence
for a claim. For example, if a person were able to inspire in a person an
incredible hatred of the claim that 1+1 = 2 and then inspired the person to
love the claim that 1+1 = 3, it would hardly follow that the claim that 1+1 = 3
would be adequately supported.
It should be noted that
in many cases it is not particularly obvious that the person committing the
fallacy is attempting to support a claim. In many cases, the user of the
fallacy will appear to be attempting to move people to take an action, such as
buying a product or fighting in a war. However, it is possible to determine
what sort of claim the person is actually attempting to support. In such cases
one needs to ask "what sort of claim is this person attempting to get
people to accept and act on?" Determining this claim (or claims) might
take some work. However, in many cases it will be quite evident. For example,
if a political leader is attempting to convince her followers to participate in
certain acts of violence by the use of a hate speech, then her claim would be
"you should participate in these acts of violence." In this case, the
"evidence" would be the hatred evoked in the followers. This hatred
would serve to make them favorable inclined towards the claim that they should
engage in the acts of violence. As another example, a beer commercial might
show happy, scantily clad men and women prancing about a beach, guzzling beer.
In this case the claim would be "you should buy this beer." The
"evidence" would be the excitement evoked by seeing the beautiful
people guzzling the beer.
This fallacy is actually
an extremely effective persuasive device. As many people have argued, peoples'
emotions often carry much more force than their reason. Logical argumentation
is often difficult and time consuming and it rarely has the power to spurn
people to action. It is the power of this fallacy that explains its great
popularity and wide usage. However, it is still a fallacy.
In all fairness it must
be noted that the use of tactics to inspire emotions is an important skill.
Without an appeal to peoples' emotions, it is often difficult to get them to
take action or to perform at their best. For example, no good coach presents
her team with syllogisms before the big game. Instead she inspires them with
emotional terms and attempts to "fire" them up. There is nothing
inherently wrong with this. However, it is not any acceptable form of argumentation.
As long as one is able to clearly distinguish between what inspires emotions
and what justifies a claim, one is unlikely to fall prey to this fallacy.
As a final point, in
many cases it will be difficult to distinguish an Appeal to Emotion from some
other fallacies and in many cases multiple fallacies may be committed. For
example, many Ad Hominems will be very similar to Appeals to Emotion and, in some cases, both
fallacies will be committed. As an example, a leader might attempt to invoke
hatred of a person to inspire his followers to accept that they should reject
her claims. The same attack could function as an Appeal to Emotion and a Personal Attack. In the first case, the attack would be aimed at making the followers
feel very favorable about rejecting her claims. In the second case, the attack
would be aimed at making the followers reject the person's claims because of
some perceived (or imagined) defect in her character.
This fallacy is related
to the Appeal to Popularity fallacy. Despite the differences between these two fallacies, they are
both united by the fact that they involve appeals to emotions. In both cases
the fallacies aim at getting people to accept claims based on how they or
others feel about the claims and not based on evidence for the claims.
Another way to look at
these two fallacies is as follows
1. Most people approve of X.
2. So, I should approve of X, too.
3. Since I approve of X, X must be true.
Appeal to Emotion
1. I approve of X.
2. Therefore, X is true.
On this view, in an Appeal to Popularity the claim is accepted because most people approve of the claim. In the
case of an Appeal to Emotion the claim is accepted because the individual
approves of the claim because of the emotion of approval he feels in regards to
the claim.
1. The new PowerTangerine computer gives you the power you need. If you buy
one, people will envy your power. They will look up to you and wish they were
just like you. You will know the true joy of power. TangerinePower.
7.
Fallacy: Appeal to Consequences of a Belief
Includes: Wishful Thinking
The Appeal to the
Consequences of a Belief is a fallacy that comes in the following patterns:
1. X is true because if people did not accept X as being true then there
would be negative consequences.
This line of "reasoning"
is fallacious because the consequences of a belief have no bearing on whether
the belief is true or false. For example, if someone were to say "If
sixteen-headed purple unicorns don't exist, then I would be miserable, so they
must exist" it would be clear that this would not be a good line of
reasoning. It is important to note that the consequences in question are the
consequences that stem from the belief. It is important to distinguish between
a rational reason to believe (RRB) (evidence) and a prudential reason to
believe (PRB) (motivation). A RRB is evidence that objectively and logically
supports the claim. A PRB is a reason to accept the belief because of some
external factor (such as fear, a threat, or a benefit or harm that may stem
from the belief) that is relevant to what a person values but is not relevant
to the truth or falsity of the claim.
The nature of the
fallacy is especially clear in the case of Wishful thinking. Obviously, merely
wishing that something is true does not make it true. This fallacy differs from
the Appeal to Belief fallacy in that the Appeal to Belief involves taking a claim that most people believe that X is true to be
evidence for X being true.
1. "God must exist! If God did not exist, then all basis for morality
would be lost and the world would be a horrible place!"
8.
Fallacy: Appeal to Flattery
Also Known as: Apple Polishing, various
"colorful" expressions.
An Appeal to Flattery is
a fallacy of the following form:
1. Person A is flattered by person B.
2. Person B makes claim X.
3. Therefore X is true.
The basic idea behind
this fallacy is that flattery is presented in the place of evidence for
accepting a claim. this sort of "reasoning" is fallacious because
flattery is not, in fact, evidence for a claim. This is especially clear in a
case like this: "My Bill, that is a really nice tie. By the way, it is quite
clear that one plus one is equal to forty three."
1. "Might I say that this is the best philosophy class I've ever
taken. By the way, about those two points I need to get an A..."
9.
Fallacy: Appeal to Fear
Also Known as: Scare Tactics, Appeal to Force, Ad
Baculum
The Appeal to Fear is a
fallacy with the following pattern:
1. Y is presented (a claim that is intended to produce fear).
2. Therefore claim X is true (a claim that is generally, but need not be,
related to Y in some manner).
This line of
"reasoning" is fallacious because creating fear in people does not
constitute evidence for a claim.
It is important to
distinguish between a rational reason to believe (RRB) (evidence) and a
prudential reason to believe (PRB) (motivation). A RRB is evidence that
objectively and logically supports the claim. A PRB is a reason to accept the
belief because of some external factor (such as fear, a threat, or a benefit or
harm that may stem from the belief) that is relevant to what a person values
but is not relevant to the truth or falsity of the claim. For example, it might
be prudent to not fail the son of your department chairperson because you fear
he will make life tough for you. However, this does not provide evidence for
the claim that the son deserves to pass the class.
1. "You know, Professor Smith, I really need to get an A in this
class. I'd like to stop by during your office hours later to discuss my grade.
I'll be in your building anyways, visiting my father. He's your dean, by the
way. I'll see you later."
10.
Fallacy: Appeal to Novelty
Also Known as: Appeal to the New, Newer is Better,
Novelty.
Appeal to Novelty is a
fallacy that occurs when it is assumed that something is better or correct
simply because it is new. This sort of "reasoning" has the following
form:
1. X is new.
2. Therefore X is correct or better.
This sort of
"reasoning" is fallacious because the novelty or newness of something
does not automatically make it correct or better than something older. This is
made quite obvious by the following example: Joe has proposed that 1+1 should
now be equal to 3. When asked why people should accept this, he says that he
just came up with the idea. Since it is newer than the idea that 1+1=2, it must
be better.
This sort of
"reasoning" is appealing for many reasons. First, "western
culture" includes a very powerful committment to the notion that new
things must be better than old things. Second, the notion of progress (which
seems to have come, in part, from the notion of evolution) implies that newer
things will be superior to older things. Third, media advertising often sends
the message that newer must be better. Because of these three factors (and
others) people often accept that a new thing (idea, product, concept, etc.)
must be better because it is new. Hence, Novelty is a somewhat common fallacy,
escpecially in advertising.
It should not be assumed
that old things must be better than new things (see the fallacy Appeal to
Tradition) anymore than it should be assumed that new things are better than
old things. The age of thing does not, in general, have any bearing on its
quality or correctness (in this context).
Obviously, age does have
a bearing in some contexts. For example, if a person concluded that his day old
milk was better than his two-month old milk, he would not be committing an
Appeal to Novelty. This is because, in such cases the newness of the thing is
relevant to its quality. Thus, the fallacy is committed only when the newness
is not, in and of itself, relevant to the claim.
1. A made up advertisement.
The Sadisike 900 pump-up glow shoe. It's
better because it's new.
James: "So, what is this new
plan?"
Biff: "Well, the latest thing in marketing techniques is the GK method. It
is the latest thing out of the think tank. It is so new that the ink on the
reports is still drying."
James: "Well, our old marketing method has been quite effective. I don't
like the idea of jumping to a new method without a good reason."
Biff: "Well, we know that we have to stay on the cutting edge. That means
new ideas and new techniques have to be used. The GK method is new, so it will
do better than that old, dusty method."
Prof: "So you can see that a new and
better morality is sweeping the nation. No longer are people with alternative
lifestyles ashamed. No longer are people caught up in the outmoded moralities
of the past."
Student: "Well, what about the ideas of the the great thinkers of the
past? Don't they have some valid points?"
Prof: "A good question. The answer is that they had some valid points in
their own, barbaric times. But those are old, mouldy moralities from a time
long gone. Now is a time for new moralities. Progress and all that, you
know."
Student: "So would you say that the new moralities are better because they
are newer?"
Prof: "Exactly. Just as the dinosaurs died off to make way for new
animals, the old ideas have to give way for the new ones. And just as humans
are better than dinosaurs, the new ideas are better than the old. So newer is
literally better."
Student: "I see."
11.
Fallacy: Appeal to Pity
Also known as: Ad Misericordiam
An Appeal to Pity is a
fallacy in which a person substitutes a claim intended to create pity for
evidence in an argument. The form of the "argument" is as follows:
1. P is presented, with the intent to create pity.
2. Therefore claim C is true.
This line of
"reasoning" is fallacious because pity does not serve as evidence for
a claim. This is extremely clear in the following case: "You must accept
that 1+1=46, after all I'm dying..." While you may pity me because I am
dying, it would hardly make my claim true.
This fallacy differs
from the Appeal to the
Consequences of a Belief (ACB). In the ACB
fallacy, a person is using the effects of a belief as a substitute for
evidence. In the Appeal to Pity, it is the feelings of pity or sympathy that
are substituted for evidence.
It must be noted that
there are cases in which claims that actually serve as evidence also evoke a
feeling of pity. In such cases, the feeling of pity is still not evidence. The
following is an example of a case in which a claim evokes pity and also serves
as legitimate evidence:
Professor: "You
missed the midterm, Bill."
Bill: "I know. I think you should let me take the makeup."
Professor: "Why?"
Bill: "I was hit by a truck on the way to the midterm. Since I had to go
to the emergency room with a broken leg, I think I am entitled to a
makeup."
Professor: "I'm sorry about the leg, Bill. Of course you can make it
up."
The above example does
not involve a fallacy. While the professor does feel sorry for Bill, she is
justified in accepting Bill's claim that he deserves a makeup. After all
getting run over by a truck would be a legitimate excuse for missing a test.
1. Jill: "He'd be a terrible coach for the team."
Bill: "He had his heart set on the job, and it would break if he didn't
get it."
Jill: "I guess he'll do an adequate job."
12.
Fallacy: Appeal to Popularity
Also Known as: Ad Populum
The Appeal to Popularity
has the following form:
1. Most people approve of X (have favorable emotions towards X).
2. Therefore X is true.
The basic idea is that a
claim is accepted as being true simply because most people are favorably
inclined towards the claim. More formally, the fact that most people have
favorable emotions associated with the claim is substituted in place of actual
evidence for the claim. A person falls prey to this fallacy if he accepts a
claim as being true simply because most other people approve of the claim.
It is clearly fallacious
to accept the approval of the majority as evidence for a claim. For example,
suppose that a skilled speaker managed to get most people to absolutely love
the claim that 1+1=3. It would still not be rational to accept this claim
simply because most people approved of it. After all, mere approval is no
substitute for a mathematical proof. At one time people approved of claims such
as "the world is flat", "humans cannot survive at speeds greater
than 25 miles per hour", "the sun revolves around the earth" but
all these claims turned out to be false.
This sort of
"reasoning" is quite common and can be quite an effective persusasive
device. Since most humans tend to conform with the views of the majority,
convincing a person that the majority approves of a claim is often an effective
way to get him to accept it. Advertisers often use this tactic when they
attempt to sell products by claiming that everyone uses and loves their
products. In such cases they hope that people will accept the (purported)
approval of others as a good reason to buy the product.
This fallacy is vaguely
similar to such fallacies as Appeal to Belief and Appeal to Common
Practice. However, in the case of an Ad Populum
the appeal is to the fact that most people approve of a claim. In the case of
an Appeal to Belief, the appeal is to the fact that most people believe a claim. In the
case of an Appeal to Common
Practice, the appeal is to the fact that many
people take the action in question.
This fallacy is closely
related to the Appeal to Emotion fallacy, as discussed in the entry for that fallacy.
1. "My fellow Americans...there has been some talk that the government
is overstepping its bounds by allowing police to enter peoples' homes without
the warrants traditionally required by the Constitution. However, these are
dangerous times and dangerous times require appropriate actions. I have in my
office thousands of letters from people who let me know, in no uncertain terms,
that they heartily endorse the war against crime in these United States.
Because of this overwhelming approval, it is evident that the police are doing
the right thing."
13.
Fallacy: Appeal to Ridicule
Also Known as: Appeal to Mockery, The Horse Laugh.
The Appeal to Ridicule
is a fallacy in which ridicule or mockery is substituted for evidence in an
"argument." This line of "reasoning" has the following
form:
1. X, which is some form of ridicule is presented (typically directed at
the claim).
2. Therefore claim C is false.
This sort of
"reasoning" is fallacious because mocking a claim does not show that
it is false. This is especially clear in the following example: "1+1=2!
That's the most ridiculous thing I have ever heard!"
It should be noted that
showing that a claim is ridiculous through the use of legitimate methods (such
as a non fallacious argument) can make it reasonable to reject the claim. One
form of this line of reasoning is known as a "reductio ad absurdum"
("reducing to absurdity"). In this sort of argument, the idea is to
show that a contradiction (a statement that must be false) or an absurd result
follows from a claim. For example: "Bill claims that a member of a
minority group cannot be a racist. However, this is absurd. Think about this:
white males are a minority in the world. Given Bill's claim, it would follow
that no white males could be racists. Hence, the Klan, Nazis, and white
supremists are not racist organizations."
Since the claim that the
Klan, Nazis, and white supremists are not racist organizations is clearly
absurd, it can be concluded that the claim that a member of a minority cannot
be a racist is false.
1. "Sure my worthy opponent claims that we should lower tuition, but
that is just laughable."
14.
Fallacy: Appeal to Spite
The Appeal to Spite
Fallacy is a fallacy in which spite is substituted for evidence when an
"argument" is made against a claim. This line of
"reasoning" has the following form:
1. Claim X is presented with the intent of generating spite.
2. Therefore claim C is false (or true)
This sort of
"reasoning" is fallacious because a feeling of spite does not count
as evidence for or against a claim. This is quite clear in the following case:
"Bill claims that the earth revolves around the sun. But remember that
dirty trick he pulled on you last week. Now, doesn't my claim that the sun
revolves around the earth make sense to you?"
Of course, there are
cases in which a claim that evokes a feeling of spite or malice can serve as
legitimate evidence. However, it should be noted that the actual feelings of
malice or spite are not evidence. The following is an example of such a situation:
Jill: "I think I'll
vote for Jane to be treasurer of NOW."
Vicki: "Remember the time that your purse vanished at a meeting last
year?"
Jill: "Yes."
Vicki:"Well, I just found out that she stole your purse and stole some
other stuff from people."
Jill: "I'm not voting for her!"
In this case, Jill has a
good reason not to vote for Jane. Since a treasurer should be honest, a known
thief would be a bad choice. As long as Jill concludes that she should vote
against Jane because she is a thief and not just out of spite, her reasoning
would not be falacious.
1. Bill: "I think that Jane did a great job this year. I'm going to
nominate her for the award."
Dave: "Have you forgotten last year? Remember that she didn't nominate you
last year."
Bill: "You're right. I'm not going to nominate her."
15.
Fallacy: Appeal to Tradition
Also Known as: Appeal to the Old, Old Ways are Best,
Fallacious Appeal to the Past, Appeal to Age
Appeal to Tradition is a
fallacy that occurs when it is assumed that something is better or correct
simply because it is older, traditional, or "always has been done."
This sort of "reasoning" has the following form:
1. X is old or traditional
2. Therefore X is correct or better.
This sort of
"reasoning" is fallacious because the age of something does not
automatically make it correct or better than something newer. This is made
quite obvious by the following example: The theory that witches and demons
cause disease is far older than the theory that microrganisms cause diseases.
Therefore, the theory about witches and demons must be true.
This sort of
"reasoning" is appealing for a variety of reasons. First, people often
prefer to stick with what is older or traditional. This is a fairly common
psychological characteristic of people which may stem from the fact that people
feel more comfortable about what has been around longer. Second, sticking with
things that are older or traditional is often easier than testing new things.
Hence, people often prefer older and traditional things out of laziness. Hence,
Appeal to Tradition is a somewhat common fallacy.
It should not be assumed
that new things must be better than old things (see the fallacy Appeal to
Novelty) any more than it should be assumed that old things are better than new
things. The age of something does not, in general, have any bearing on its
quality or correctness (in this context). In the case of tradition, assuming
that something is correct just because it is considered a tradition is poor
reasoning. For example, if the belief that 1+1 = 56 were a tradition of a group
of people it would hardly follow that it is true.
Obviously, age does have
a bearing in some contexts. For example, if a person concluded that aged wine
would be better than brand new wine, he would not be committing an Appeal to
Tradition. This is because, in such cases the age of the thing is relevant to
its quality. Thus, the fallacy is committed only when the age is not, in and of
itself, relevant to the claim.
One final issue that
must be considered is the "test of time." In some cases people might
be assuming that because something has lasted as a tradition or has been around
a long time that it is true because it has "passed the test of time."
If a person assumes that something must be correct or true simply because it
has persisted a long time, then he has committed an Appeal to Tradition. After
all, as history has shown people can persist in accepting false claims for
centuries.
However, if a person
argues that the claim or thing in question has successfully stood up to
challenges and tests for a long period of time then they would not be
committing a fallacy. In such cases the claim would be backed by evidence. As
an example, the theory that matter is made of subatomic particles has survived
numerous tests and challenges over the years so there is a weight of evidence
in its favor. The claim is reasonable to accept because of the weight of this
evidence and not because the claim is old. Thus, a claim's surviving legitimate
challenges and passing valid tests for a long period of time can justify the
acceptance of a claim. But mere age or persistance does not warrant accepting a
claim.
1. Sure I believe in God. People have believed in God for thousands of
years so it seems clear that God must exist. After all, why else would the
belief last so long?
Connan: "You know father, when I was
going to school in the United States I saw that American women are not treated
as property. In fact, I read a book by this person named Mill in which he
argued for women's rights."
Gunthar: "So, what is your point son?"
Connan: "Well, I think that it might be wrong to trade my sisters for
cattle. They are human beings and should have a right to be masters of their
own fate."
Gunthar: "What a strange and new-fangled notion you picked up in America.
That country must be even more barbaric then I imagined. Now think about this
son. We have been trading women for cattle for as long as our people have lived
on this island. It is a tradition that goes back into the mists of time. "
Connan: "But I still think there is something wrong with it."
Gunthar: "Nonsense my boy. A tradition this old must be endorsed by the
gods and must be right."
Reporter: "Mr. Hatfield, why are you
still fighting it out with the Mcoys?"
Hatfield: "Well you see young man, my father feuded with the Mcoys and his
father feuded with them and so did my great grandfather."
Reporter: "But why? What started all this?"
Hatfield: "I don't rightly know. I'm sure it was the Mcoys who started it
all, though."
Reporter: "If you don't know why you're fighting, why don't you just
stop?"
Hatfield: "Stop? What are you crazy? This feud has been going on for
generations so I'm sure there is a darn good reason why it started. So I aim to
keep it going. It has got to be the right thing to do. Hand me my shooting iron
boy, I see one of those Mcoy skunks sneaking in the cornfield."
16.
Fallacy: Bandwagon
Also Known as: Peer Pressure.
The Bandwagon is a
fallacy in which a threat of rejection by one's peers (or peer pressure) is
substituted for evidence in an "argument." This line of
"reasoning" has the following form:
1. Person P is pressured by his/her peers or threatened with rejection.
2. Therefore person P's claim X is false.
This line of
"reasoning" is fallacious because peer pressure and threat of
rejection do not constitute evidence for rejecting a claim. This is expecially
clear in the following example:
Joe:
"Bill, I know you think that 1+1=2. But we don't accept that sort of thing
in our group. "
Bill: "I was just joking. Of course I don't believe that."
It is clear that the
pressure from Bill's group has no bearing on the truth of the claim that 1+1=2.
It should be noted that
loyalty to a group and the need to belong can give people very strong reasons
to conform to the views and positions of those groups. Further, from a
practical standpoint we must often compromise our beliefs in order to belong to
groups. However, this feeling of loyalty or the need to belong simply do not
constitute evidence for a claim.
1. Bill says that he likes the idea that people should work for their
welfare when they can. His friends laugh at him, accuse him of fascist leanings,
and threaten to ostracize him from their group. He decides to recant and
abandon his position to avoid rejection.
17.
Fallacy: Begging the Question
Also Known as: Circular Reasoning, Reasoning in a
Circle, Petitio Principii.
Begging the Question is
a fallacy in which the premises include the claim that the conclusion is true
or (directly or indirectly) assume that the conclusion is true. This sort of
"reasoning" typically has the following form.
1. Premises in which the truth of the conclusion is claimed or the truth of
the conclusion is assumed (either directly or indirectly).
2. Claim C (the conclusion) is true.
This sort of
"reasoning" is fallacious because simply assuming that the conclusion
is true (directly or indirectly) in the premises does not constitute evidence
for that conclusion. Obviously, simply assuming a claim is true does not serve
as evidence for that claim. This is especially clear in particularly blatant
cases: "X is true. The evidence for this claim is that X is true."
Some cases of question
begging are fairly blatant, while others can be extremely subtle.
1. Bill: "God must exist."
Jill: "How do you know."
Bill: "Because the Bible says so."
Jill: "Why should I believe the Bible?"
Bill: "Because the Bible was written by God."
18.
Fallacy: Biased Sample
Also Known as: Biased Statistics, Loaded Sample, Prejudiced
Statistics, Prejudiced Sample, Loaded Statistics, Biased Induction, Biased
Generalization
This fallacy is
committed when a person draws a conclusion about a population based on a sample
that is biased or prejudiced in some manner. It has the following form:
1. Sample S, which is biased, is taken from population P.
2. Conclusion C is drawn about Population P based on S.
The person committing
the fallacy is misusing the following type of reasoning, which is known
variously as Inductive Generalization, Generalization, and Statistical
Generalization:
1. X% of all observed A's are B''s.
2. Therefore X% of all A's are Bs.
The fallacy is committed
when the sample of A's is likely to be biased in some manner. A sample is
biased or loaded when the method used to take the sample is likely to result in
a sample that does not adequately represent the population from which it is
drawn.
Biased samples are
generally not very reliable. As a blatant case, imagine that a person is taking
a sample from a truckload of small colored balls, some of which are metal and
some of which are plastic. If he used a magnet to select his sample, then his
sample would include a disproportionate number of metal balls (after all, the
sample will probably be made up entirely of the metal balls). In this case, any
conclusions he might draw about the whole population of balls would be
unreliable since he would have few or no plastic balls in the sample.
The general idea is that
biased samples are less likely to contain numbers proportional to the whole
population. For example, if a person wants to find out what most Americans
thought about gun control, a poll taken at an NRA meeting would be a biased
sample.
Since the Biased Sample
fallacy is committed when the sample (the observed instances) is biased or
loaded, it is important to have samples that are not biased making a
generalization. The best way to do this is to take samples in ways that avoid
bias. There are, in general, three types of samples that are aimed at avoiding
bias. The general idea is that these methods (when used properly) will result
in a sample that matches the whole population fairly closely. The three types
of samples are as follows
1. Random Sample: This is a sample that is taken in such a way that nothing
but chance determines which members of the population are selected for the
sample. Ideally, any individual member of the population has the same chance as
being selected as any other. This type of sample avoids being biased because a
biased sample is one that is taken in such a way that some members of the
population have a significantly greater chance of being selected for the sample
than other members. Unfortunately, creating an ideal random sample is often
very difficult.
People often commit
Biased Sample because of bias or prejudice. For example, a person might
intentionally or unintentionally seek out people or events that support his
bias. As an example, a person who is pushing a particular scientific theory
might tend to gather samples that are biased in favor of that theory.
People also commonly
commit this fallacy because of laziness or sloppiness. It is very easy to
simply take a sample from what happens to be easily available rather than
taking the time and effort to generate an adequate sample and draw a justified
conclusion.
It is important to keep
in mind that bias is relative to the purpose of the sample. For example, if
Bill wanted to know what NRA members thought about a gun control law, then
taking a sampleat a NRA meeting would not be biased. However, if Bill wanted to
determine what Americans in general thought about the law, then a sample taken
at an NRA meeting would be biased.
1. Bill is assigned by his editor to determine what most Americans think
about a new law that will place a federal tax on all modems and computers
purchased. The revenues from the tax will be used to enforce new online decency
laws. Bill, being technically inclined, decides to use an email poll. In his
poll, 95% of those surveyed opposed the tax. Bill was quite surprised when 65%
of all Americans voted for the taxes.
19.
Fallacy: Burden of Proof
Includes: Appeal to Ignorance ("Ad
Ignorantiam")
Burden of Proof is a
fallacy in which the burden of proof is placed on the wrong side. Another
version occurs when a lack of evidence for side A is taken to be evidence for
side B in cases in which the burden of proof actually rests on side B. A common
name for this is an Appeal to Ignorance. This sort of reasoning typically has
the following form:
1. Claim X is presented by side A and the burden of proof actually rests on
side B.
2. Side B claims that X is false because there is no proof for X.
In many situations, one
side has the burden of proof resting on it. This side is obligated to provide
evidence for its position. The claim of the other side, the one that does not
bear the burden of proof, is assumed to be true unless proven otherwise. The
difficulty in such cases is determining which side, if any, the burden of proof
rests on. In many cases, settling this issue can be a matter of significant
debate. In some cases the burden of proof is set by the situation. For example,
in American law a person is assumed to be innocent until proven guilty (hence
the burden of proof is on the prosecution). As another example, in debate the
burden of proof is placed on the affirmative team. As a final example, in most
cases the burden of proof rests on those who claim something exists (such as
Bigfoot, psychic powers, universals, and sense data).
1. Bill: "I think that we should invest more money in expanding the
interstate system."
Jill: "I think that would be a bad idea, considering the state of the
treasury."
Bill: "How can anyone be against highway improvements?"
20.
Fallacy: Circumstantial Ad Hominem
A Circumstantial ad
Hominem is a fallacy in which one attempts to attack a claim by asserting that
the person making the claim is making it simply out of self interest. In some
cases, this fallacy involves substituting an attack on a person's circumstances
(such as the person's religion, political affiliation, ethnic background,
etc.). The fallacy has the following forms:
1. Person A makes claim X.
2. Person B asserts that A makes claim X because it is in A's interest to
claim X.
3. Therefore claim X is false.
1. Person A makes claim X.
2. Person B makes an attack on A's circumstances.
3. Therefore X is false.
A Circumstantial ad
Hominem is a fallacy because a person's interests and circumstances have no
bearing on the truth or falsity of the claim being made. While a person's
interests will provide them with motives to support certain claims, the claims
stand or fall on their own. It is also the case that a person's circumstances (religion,
political affiliation, etc.) do not affect the truth or falsity of the claim.
This is made quite clear by the following example: "Bill claims that
1+1=2. But he is a Republican, so his claim is false."
There are times when it
is prudent to suspicious of a person's claims, such as when it is evident that
the claims are being biased by the person's interests. For example, if a
tobacco company representative claims that tobacco does not cause cancer, it
would be prudent to not simply accept the claim. This is because the person has
a motivation to make the claim, whether it is true or not. However, the mere
fact that the person has a motivation to make the claim does not make it false.
For example, suppose a parent tells her son that sticking a fork in a light
socket would be dangerous. Simply because she has a motivation to say this
obviously does not make her claim false.
1. "She asserts that we need more military spending, but that is
false, since she is only saying it because she is a Republican."
21.
Fallacy: Confusing Cause and Effect
Also Known as: Questionable Cause
Confusing Cause and
Effect is a fallacy that has the following general form:
1. A and B regularly occur together.
2. Therefore A is the cause of B.
This fallacy requires
that there is not, in fact, a common cause that actually causes both A and B.
This fallacy is
committed when a person assumes that one event must cause another just because
the events occur together. More formally, this fallacy involves drawing the
conclusion that A is the cause of B simply because A and B are in regular
conjunction (and there is not a common cause that is actually the cause of A
and B). The mistake being made is that the causal conclusion is being drawn
without adequate justification.
In some cases it will be
evident that the fallacy is being committed. For example, a person might claim
that an illness was caused by a person getting a fever. In this case, it would
be quite clear that the fever was caused by illness and not the other way
around. In other cases, the fallacy is not always evident. One factor that
makes causal reasoning quite difficult is that it is not always evident what is
the cause and what is the effect. For example, a problem child might be the
cause of the parents being short tempered or the short temper of the parents
might be the cause of the child being problematic. The difficulty is increased
by the fact that some situations might involve feedback. For example, the
parents' temper might cause the child to become problematic and the child's
behavior could worsen the parents' temper. In such cases it could be rather
difficult to sort out what caused what in the first place.
In order to determine
that the fallacy has been committed, it must be shown that the causal
conclusion has not been adequately supported and that the person committing the
fallacy has confused the actual cause with the effect. Showing that the fallacy
has been committed will typically involve determining the actual cause and the
actual effect. In some cases, as noted above, this can be quite easy. In other
cases it will be difficult. In some cases, it might be almost impossible.
Another thing that makes causal reasoning difficult is that people often have
very different conceptions of cause and, in some cases, the issues are clouded
by emotions and ideologies. For example, people often claim violence on TV and
in movies must be censored because it causes people to like violence. Other
people claim that there is violence on TV and in movies because people like
violence. In this case, it is not obvious what the cause really is and the
issue is clouded by the fact that emotions often run high on this issue.
While causal reasoning
can be difficult, many errors can be avoided with due care and careful testing
procedures. This is due to the fact that the fallacy arises because the
conclusion is drawn without due care. One way to avoid the fallacy is to pay
careful attention to the temporal sequence of events. Since (outside of Star
Trek), effects do not generally precede their causes, if A occurs after B, then
A cannot be the cause of B. However, these methods go beyond the scope of this
program.
All causal fallacies
involve an error in causal reasoning. However, this fallacy differs from the
other causal fallacies in terms of the error in reasoning being made. In the
case of a Post Hoc fallacy, the error is that a person is accepting that A is the cause of
B simply because A occurs before B. In the case of the Fallacy of Ignoring a Common Cause A is taken to be the cause of B when there is, in fact, a third factor
that is the cause of both A and B. For more information, see the relevant
entries in this program.
1. Bill and Joe are having a debate about music and moral decay:
Bill: "It seems clear to me that this new music is causing the youth to
become corrupt."
Joe: "What do you mean?"
Bill: "This rap stuff is always telling the kids to kill cops, do drugs,
and abuse women. That is all bad and the kids today shouldn't be doing that sort
of stuff. We ought to ban that music!"
Joe: "So, you think that getting rid of the rap music would solve the
drug, violence and sexism problems in the US?"
Bill: "Well, it wouldn't get rid of it all, but it would take care of a
lot of it."
Joe: "Don't you think that most of the rap singers sing about that sort of
stuff because that is what is really going on these days? I mean, people often
sing about the conditions of their time, just like the people did in the
sixties. But then I suppose that you think that people were against the war and
into drugs just because they listened to Dylan and Baez."
Bill: "Well..."
Joe: "Well, it seems to me that the main cause of the content of the rap
music is the pre-existing social conditions. If there weren't all these
problems, the rap singers probably wouldn't be singing about them. I also think
that if the social conditions were great, kids could listen to the music all
day and not be affected."
Bill: "Well, I still think the rap music causes the problems. You can't
argue against the fact that social ills really picked up at the same time rap
music got started."
22.
Fallacy: Division
The fallacy of Division
is committed when a person infers that what is true of a whole must also be
true of its constituents and justification for that inference is not provided.
There are two main
variants of the general fallacy of Division:
The first type of
fallacy of Division is committed when 1) a person reasons that what is true of
the whole must also be true of the parts and 2) the person fails to justify
that inference with the required degree of evidence. More formally, the
"reasoning" follows this sort of pattern:
1. The whole, X, has properties A, B, C, etc.
2. Therefore the parts of X have properties A, B, C, etc.
That this line of
reasoning is fallacious is made clear by the following case: 4 is an even
number. 1 and 3 are parts of 4. Therefore 1 and 3 are even.
It should be noted that
it is not always fallacious to draw a conclusion about the parts of a whole
based on the properties of the whole. As long as adequate evidence is provided
in the argument, the the reasoning can be acceptable. For example, the human
body is made out of matter and it is reasonable to infer from this that the
parts that make up the human body are also made out of matter. This is because
there is no reason to believe that the body is made up of non-material parts
that somehow form matter when they get together.
The second version of
the fallacy of division is committed when a person 1) draws a conclusion about
the properties of indvidual members of a class or group based on the collective
properties of the class or group and 2) there is not enough justification for
the conclusion. More formally, the line of "reasoning" is as follows:
1. As a collective, Group or class X has properties A, B, C, etc.
2. Therefore the individual members of group or class X have properties A,
B, C, etc.
That this sort of
reasoning is fallacious can be easily shown by the following: It is true that
athletes, taken as a group, are football players, track runners, swimmers,
tennis players, long jumpers, pole vaulters and such. But it would be
fallacious to infer that each individual athlets is a football player, a track
runner, a swimmer, a tennis player, a swimmer, etc.
It should be noted that
it is not always fallacious to draw a conclusion about an individual based on
what is true of the class he/she/it belongs to. If the inference is backed by
evidence, then the reasoning can be fine. For example, it is not fallacious to
infer that Bill the Siamese cat is a mammal from the fact that all cats are
mammals. In this case, what is true of the class is also true of each
individual member.
1. "The ball is blue, therefore the atoms that make it up are also
blue."
23.
Fallacy: False Dilemma
Also Known as: Black & White Thinking.
A False Dilemma is a
fallacy in which a person uses the following pattern of "reasoning":
1. Either claim X is true or claim Y is true (when X and Y could both be
false).
2. Claim Y is false.
3. Therefore claim X is true.
This line of
"reasoning" is fallacious because if both claims could be false, then
it cannot be inferred that one is true because the other is false. That this is
the case is made clear by the following example:
1. Either 1+1=4 or 1+1=12.
2. It is not the case that 1+1=4.
3. Therefore 1+1=12.
In cases in which the
two options are, in fact, the only two options, this line of reasoning is not
fallacious. For example:
1. Bill is dead or he is alive.
2. Bill is not dead.
3. Therefore Bill is alive.
1. Senator Jill: "We'll have to cut education funding this year."
Senator Bill: "Why?"
Senator Jill: "Well, either we cut the social programs or we live with a
huge deficit and we can't live with the deficit."
24.
Fallacy: Guilt By Association
Also Known as: Bad Company Fallacy, Company that You
Keep Fallacy
Guilt by Association is
a fallacy in which a person rejects a claim simply because it is pointed out
that people she dislikes accept the claim. This sort of "reasoning"
has the following form:
1. It is pointed out that people person A does not like accept claim P.
2. Therefore P is false
It is clear that sort of
"reasoning" is fallacious. For example the following is obviously a
case of poor "reasoning": "You think that 1+1=2. But, Adolf
Hitler, Charles Manson, Joseph Stalin, and Ted Bundy all believed that 1+1=2.
So, you shouldn't believe it."
The fallacy draws its
power from the fact that people do not like to be associated with people they
dislike. Hence, if it is shown that a person shares a belief with people he
dislikes he might be influenced into rejecting that belief. In such cases the
person will be rejecting the claim based on how he thinks or feels about the
people who hold it and because he does not want to be associated with such
people.
Of course, the fact that
someone does not want to be associated with people she dislikes does not
justify the rejection of any claim. For example, most wicked and terrible
people accept that the earth revolves around the sun and that lead is heavier
than helium. No sane person would reject these claims simply because this would
put them in the company of people they dislike (or even hate).
1. Will and Kiteena are arguing over socialism. Kiteena is a pacifist and
hates violence and violent people.
Kiteena: "I think that the United
States should continue to adopt socialist programs. For example, I think that
the government should take control of vital industries."
Will: "So, you are for state ownership of industry."
Kiteena: "Certainly. It is a great idea and will help make the world a
less violent place."
Will: "Well, you know Stalin also endorsed state ownership on industry. At
last count he wiped out millions of his own people. Pol Pot of Cambodia was
also for state ownership of industry. He also killed millions of his own
people. The leadership of China is for state owned industry. They killed their
own people in that square. So, are you still for state ownership of
industry?"
Kiteena: "Oh, no! I don't want to be associated with those butchers!"
Jen: "I was reading over some private
studies of welfare and I think it would be better to have people work for their
welfare. For example, people could pick up trash, put up signs, and maybe even
do skilled labor that they are qualified for. This would probably make people
feel better about themselves and it would get more out of our tax money."
Sandy: "I see. So, you want to have the poor people out on the streets
picking up trash for their checks? Well, you know that is exactly the position
David Count endorses."
Jen: "Who is he?"
Sandy: "I'm surprised you don't know him, seeing how alike you two are. He
was a Grand Mooky Wizard for the Aryan Pure White League and is well known for
his hatred of blacks and other minorities. With your views, you'd fit right in
to his little racist club."
Jen: "So, I should reject my view just because I share it with some
racist?"
Sandy: "Of course."
Ferris: "So, who are you going to
vote for?"
Libard: "Well, I was thinking about voting for Jane, since she is a woman
and there has never been a woman chair here. But, I think that Steve will do an
excellent job. He has a lot of clout in the university and he is a decent
person."
Ferris: "You know, Wayne and Bill are supporting him. They really like the
idea of having Steve as the new chair. I never thought I'd see you and those
two pigs on the same side."
Libard: "Well, maybe it is time that we have a woman as chair."
25.
Fallacy: Gambler's Fallacy
The Gambler's Fallacy is
committed when a person assumes that a departure from what occurs on average or
in the long term will be corrected in the short term. The form of the fallacy
is as follows:
1. X has happened.
2. X departs from what is expected to occur on average or over the long
term.
3. Therefore, X will come to an end soon.
There are two common
ways this fallacy is committed. In both cases a person is assuming that some
result must be "due" simply because what has previously happened
departs from what would be expected on average or over the long term.
The first involves
events whose probabilities of occuring are independent of one another. For
example, one toss of a fair (two sides, non-loaded) coin does not affect the
next toss of the coin. So, each time the coin is tossed there is (ideally) a
50% chance of it landing heads and a 50% chance of it landing tails. Suppose
that a person tosses a coin 6 times and gets a head each time. If he concludes
that the next toss will be tails because tails "is due", then he will
have committed the Gambler's Fallacy. This is because the results of previous
tosses have no bearing on the outcome of the 7th toss. It has a 50% chance of
being heads and a 50% chance of being tails, just like any other toss.
The second involves
cases whose probabilities of occuring are not independent of one another. For
example, suppose that a boxer has won 50% of his fights over the past two
years. Suppose that after several fights he has won 50% of his matches this
year, that he his lost his last six fights and he has six left. If a person
believed that he would win his next six fights because he has used up his
losses and is "due" for a victory, then he would have committed the
Gambler's Fallacy. After all, the person would be ignoring the fact that the
results of one match can influence the results of the next one. For example,
the boxer might have been injured in one match which would lower his chances of
winning his last six fights.
It should be noted that
not all predictions about what is likely to occur are fallacious. If a person
has good evidence for his predictions, then they will be reasonable to accept.
For example, if a person tosses a fair coin and gets nine heads in a row it
would be reasonable for him to conclude that he will probably not get another
nine in a row again. This reasoning would not be fallacious as long as he
believed his conclusion because of an understanding of the laws of probability.
In this case, if he concluded that he would not get another nine heads in a row
because the odds of getting nine heads in a row are lower than getting fewer
than nine heads in a row, then his reasoning would be good and his conclusion
would be justified. Hence, determining whether or not the Gambler's Fallacy is
being committed often requires some basic understanding of the laws of
probability.
1. Bill is playing against Doug in a WWII tank battle game. Doug has had a
great "streak of luck" and has been killing Bill's tanks left and
right with good die rolls. Bill, who has a few tanks left, decides to risk all
in a desperate attack on Doug. He is a bit worried that Doug might wipe him
out, but he thinks that since Doug's luck at rolling has been great Doug must
be due for some bad dice rolls. Bill launches his attack and Doug butchers his
forces.
Jane: "I'll be able to buy that car I
always wanted soon."
Bill: "Why, did you get a raise?"
Jane: "No. But you know how I've been playing the lottery all these
years?"
Bill: "Yes, you buy a ticket for every drawing, without fail."
Jane: "And I've lost every time."
Bill: "So why do you think you will win this time?"
Jane: "Well, after all those losses I'm due for a win."
Joe: "You see that horse over there?
He lost his last four races. I'm going to bet on him."
Sam: "Why? I think he will probably lose."
Joe: "No way, Sam. I looked up the horse's stats and he has won half his
races in the past two years. Since he has lost three of his last four races,
he'll have to win this race. So I'm betting the farm on him."
Sam: "Are you sure?"
Joe: "Of course I'm sure. That pony is due, man...he's due!"
26.
Fallacy: Middle Ground
Also Known as: Golden Mean Fallacy, Fallacy of
Moderation
This fallacy is
committed when it is assumed that the middle position between two extremes must
be correct simply because it is the middle position. this sort of
"reasoning" has the following form:
1. Position A and B are two extreme positions.
2. C is a position that rests in the middle between A and B.
3. Therefore C is the correct position.
This line of
"reasoning" is fallacious because it does not follow that a position
is correct just because it lies in the middle of two extremes. This is shown by
the following example. Suppose that a person is selling his computer. He wants
to sell it for the current market value, which is $800 and someone offers him
$1 for it. It would hardly follow that $400.50 is the proper price.
This fallacy draws its
power from the fact that a moderate or middle position is often the correct
one. For example, a moderate amount of exercise is better than too much
exercise or too little exercise. However, this is not simply because it lies in
the middle ground between two extremes. It is because too much exercise is
harmful and too little exercise is all but useless. The basic idea behind many
cases in which moderation is correct is that the extremes are typically "too
much" and "not enough" and the middle position is
"enough." In such cases the middle position is correct almost by
definition.
It should be kept in
mind that while uncritically assuming that the middle position must be correct
because it is the middle position is poor reasoning it does not follow that
accepting a middle position is always fallacious. As was just mentioned, many
times a moderate position is correct. However, the claim that the moderate or
middle position is correct must be supported by legitimate reasoning.
1. Some people claim that God is all powerful, all knowing, and all good.
Other people claim that God does not exist at all. Now, it seems reasonable to
accept a position somewhere in the middle. So, it is likely that God exists,
but that he is only very powerful, very knowing, and very good. That seems
right to me.
27.
Fallacy: Hasty Generalization
Also Known as: Fallacy of Insufficient Statistics,
Fallacy of Insufficient Sample, Leaping to A Conclusion, Hasty Induction.
This fallacy is
committed when a person draws a conclusion about a population based on a sample
that is not large enough. It has the following form:
1. Sample S, which is too small, is taken from population P.
2. Conclusion C is drawn about Population P based on S.
The person committing
the fallacy is misusing the following type of reasoning, which is known
variously as Inductive Generalization, Generalization, and Statistical
Generalization:
1. X% of all observed A's are B''s.
2. Therefore X% of all A's are Bs.
The fallacy is committed
when not enough A's are observed to warrant the conclusion. If enough A's are
observed then the reasoning is not fallacious.
Small samples will tend
to be unrepresentative. As a blatant case, asking one person what she thinks
about gun control would clearly not provide an adequate sized sample for
determing what Canadians in general think about the issue. The general idea is
that small samples are less likely to contain numbers proportional to the whole
population. For example, if a bucket contains blue, red, green and orange
marbles, then a sample of three marbles cannot possible be representative of the
whole population of marbles. As the sample size of marbles increases the more
likely it becomes that marbles of each color will be selected in proprtion to
their numbers in the whole population. The same holds true for things others
than marbles, such as people and their political views.
Since Hasty
Generalization is committed when the sample (the observed instances) is too
small, it is important to have samples that are large enough when making a
generalization. The most reliable way to do this is to take as large a sample
as is practical. There are no fixed numbers as to what counts as being large
enough. If the population in question is not very diverse (a population of
cloned mice, for example) then a very small sample would suffice. If the
population is very diverse (people, for example) then a fairly large sample
would be needed. The size of the sample also depends on the size of the
population. Obviously, a very small population will not support a huge sample.
Finally, the required size will depend on the purpose of the sample. If Bill
wants to know what Joe and Jane think about gun control, then a sample
consisting of Bill and Jane would (obviously) be large enough. If Bill wants to
know what most Australians think about gun control, then a sample consisting of
Bill and Jane would be far too small.
People often commit
Hasty Generalizations because of bias or prejudice. For example, someone who is
a sexist might conclude that all women are unfit to fly jet fighters because
one woman crashed one. People also commonly commit Hasty Generalizations
because of laziness or sloppiness. It is very easy to simply leap to a
conclusion and much harder to gather an adequate sample and draw a justified
conclusion. Thus, avoiding this fallacy requires minimizing the influence of
bias and taking care to select a sample that is large enough.
One final point: a Hasty
Generalization, like any fallacy, might have a true conclusion. However, as
long as the reasoning is fallacious there is no reason to accept the conclusion
based on that reasoning.
1. Smith, who is from England, decides to attend graduate school at Ohio
State University. He has never been to the US before. The day after he arrives,
he is walking back from an orientation session and sees two white (albino)
squirrels chasing each other around a tree. In his next letter home, he tells
his family that American squirrels are white.
28.
Fallacy: Ignoring a Common Cause
Also Known as: Questionable Cause
This fallacy has the
following general structure:
1. A and B are regularly connected (but no third, common cause is looked
for).
2. Therefore A is the cause of B.
This fallacy is
committed when it is concluded that one thing causes another simply because
they are regularly associated. More formally, this fallacy is committed when it
is concluded that A is the cause of B simply because A and B are regularly
connected. Further, the causal conclusion is drawn without considering the
possibility that a third factor might be the cause of both A and B.
In many cases, the
fallacy is quite evident. For example, if a person claimed that a person's
sneezing was caused by her watery eyes and he simply ignored the fact that the
woman was standing in a hay field, he would have fallen prey to the fallacy of
ignoring a common cause. In this case, it would be reasonable to conclude that
the woman's sneezing and watering eyes was caused by an allergic reaction of
some kind. In other cases, it is not as evident that the fallacy is being
comitted. For example, a doctor might find a large amount of bacteria in one of
her patients and conclude that the bacteria are the cause of the patient's illness.
However, it might turn out that the bacteria are actually harmless and that a
virus is weakening the person, Thus, the viruses would be the actual cause of
the illness and growth of the bacteria (the viruses would weaken the ability of
the person's body to resist the growth of the bacteria).
As noted in the
discussion of other causal fallacies, causality is a rather difficult matter.
However, it is possible to avoid this fallacy by taking due care. In the case
of Ignoring a Common Cause, the key to avoiding this fallacy is to be careful
to check for other factors that might be the actual cause of both the suspected
cause and the suspected effect. If a person fails to check for the possibility
of a common cause, then they will commit this fallacy. Thus, it is always a
good idea to always ask "could there be a third factor that is actually
causing both A and B?"
1. One day Bill wakes up with a fever. A few hours later he finds red spots
on his skin. he concludes that the fever must have caused the red spots. His
friend insists that the spots and the fever are caused by some microbe. Bill
laughs at this and insists that if he spends the day in a tub of cold water his
spots will go away.
28.
Fallacy: Red Herring
Also Known as: Smoke Screen, Wild Goose Chase.
A Red Herring is a fallacy
in which an irrelevant topic is presented in order to divert attention from the
original issue. The basic idea is to "win" an argument by leading
attention away from the argument and to another topic. This sort of
"reasoning" has the following form:
1. Topic A is under discussion.
2. Topic B is introduced under the guise of being relevant to topic A (when
topic B is actually not relevant to topic A).
3. Topic A is abandoned.
This sort of
"reasoning" is fallacious because merely changing the topic of discussion
hardly counts as an argument against a claim.
·
"We admit that this measure is popular. But we also urge you to
note that there are so many bond issues on this ballot that the whole thing is
getting ridiculous."
· "Argument" for a tax cut:
"You know, I've
begun to think that there is some merit in the Republican's tax cut plan. I
suggest that you come up with something like it, because If we Democrats are
going to survive as a party, we have got to show that we are as tough-minded as
the Republicans, since that is what the public wants."
· "Argument" for making grad school
requirements stricter:
"I think there is
great merit in making the requirements stricter for the graduate students. I
recommend that you support it, too. After all, we are in a budget crisis and we
do not want our salaries affected."
29.
Fallacy: Post Hoc
Also Known as: Post Hoc Ergo Propter Hoc, False Cause,
Questionable Cause, Confusing Coincidental Relationships With Causes
A Post Hoc is a fallacy
with the following form:
1. A occurs before B.
2. Therefore A is the cause of B.
The Post Hoc fallacy
derives its name from the Latin phrase "Post hoc, ergo propter hoc."
This has been traditionally interpreted as "After this, therefore because
of this." This fallacy is committed when it is concluded that one event
causes another simply because the proposed cause occurred before the proposed
effect. More formally, the fallacy involves concluding that A causes or caused
B because A occurs before B and there is not sufficient evidence to actually
warrant such a claim.
It is evident in many
cases that the mere fact that A occurs before B in no way indicates a causal
relationship. For example, suppose Jill, who is in London, sneezed at the exact
same time an earthquake started in California. It would clearly be irrational
to arrest Jill for starting a natural disaster, since there is no reason to
suspect any causal connection between the two events. While such cases are
quite obvious, the Post Hoc fallacy is fairly common because there are cases in
which there might be some connection between the events. For example, a person
who has her computer crash after she installs a new piece of software would
probably suspect that the software was to blame. If she simply concluded that
the software caused the crash because it was installed before the crash she
would be committing the Post Hoc fallacy. In such cases the fallacy would be
committed because the evidence provided fails to justify acceptance of the
causal claim. It is even theoretically possible for the fallacy to be committed
when A really does cause B, provided that the "evidence" given
consists only of the claim that A occured before B. The key to the Post Hoc
fallacy is not that there is no causal connection between A and B. It is that
adequate evidence has not been provided for a claim that A causes B. Thus, Post
Hoc resembles a Hasty Generalization in that it involves making a leap to an
unwarranted conclusion. In the case of the Post Hoc fallacy, that leap is to a
causal claim instead of a general proposition.
Not surprisingly, many
superstitions are probably based on Post Hoc reasoning. For example, suppose a
person buys a good luck charm, does well on his exam, and then concludes that
the good luck charm caused him to do well. This person would have fallen victim
to the Post Hoc fallacy. This is not to say that all "superstitions"
have no basis at all. For example, some "folk cures" have actually
been found to work.
Post Hoc fallacies are
typically committed because people are simply not careful enough when they
reason. Leaping to a causal conclusion is always easier and faster than
actually investigating the phenomenon. However, such leaps tend to land far
from the truth of the matter. Because Post Hoc fallacies are committed by
drawing an unjustified causal conclusion, the key to avoiding them is careful
investigation. While it is true that causes proceed effects (outside of Star
Trek, anyways), it is not true that precedence makes something a cause of
something else. Because of this, a causal investigation should begin with
finding what occurs before the effect in question, but it should not end there.
1. I had been doing pretty poorly this season. Then my girlfriend gave me
this neon laces for my spikes and I won my next three races. Those laces must
be good luck...if I keep on wearing them I can't help but win!
30.
Fallacy: Personal Attack
Also Known as: Ad Hominem Abusive.
A personal attack is
committed when a person substitutes abusive remarks for evidence when attacking
another person's claim or claims. This line of "reasoning" is
fallacious because the attack is directed at the person making the claim and
not the claim itself. The truth value of a claim is independent of the person
making the claim. After all, no matter how repugnant an individual might be, he
or she can still make true claims.
Not all ad Hominems are
fallacious. In some cases, an individual's characteristics can have a bearing
on the question of the veracity of her claims. For example, if someone is shown
to be a pathological liar, then what he says can be considered to be
unreliable. However, such attacks are weak, since even pathological liars might
speak the truth on occasion.
In general, it is best
to focus one's attention on the content of the claim and not on who made the
claim. It is the content that determines the truth of the claim and not the
characteristics of the person making the claim.
1. In a school debate, Bill claims that the President's economic plan is
unrealistic. His opponent, a professor, retorts by saying "the freshman
has his facts wrong."
31.
Fallacy: Two Wrongs Make a Right
Two Wrongs Make a Right
is a fallacy in which a person "justifies" an action against a person
by asserting that the person would do the same thing to him/her, when the
action is not necessary to prevent B from doing X to A. This fallacy has the
following pattern of "reasoning":
1. It is claimed that person B would do X to person A.
2. It is acceptable for person A to do X to person B (when A's doing X to B
is not necessary to prevent B from doing X to A).
This sort of
"reasoning" is fallacious because an action that is wrong is wrong
even if another person would also do it.
It should be noted that
it can be the case that it is not wrong for A to do X to B if X is done to
prevent B from doing X to A or if X is done in justified retribution. For
example, if Sally is running in the park and Biff tries to attack her, Sally
would eb jsutified in attacking Biff to defend herself. As another example, if
country A is planning to invade country B in order to enslave the people, then
country B would be justified in launching a pre-emptive strike to prevent the
invasion.
1. Bill has borrowed Jane's expensive pen, but found he didn't return it.
He tell's himself that it is okay to keep it, since she would have taken his.
32.
Fallacy: Slippery Slope
Also Known as: The Camel's Nose.
The Slippery Slope is a
fallacy in which a person asserts that some event must inevitably follow from
another without any argument for the inevitability of the event in question. In
most cases, there are a series of steps or gradations between one event and the
one in question and no reason is given as to why the intervening steps or
gradations will simply be bypassed. This "argument" has the following
form:
1. Event X has occurred (or will or might occur).
2. Therefore event Y will inevitably happen.
This sort of
"reasoning" is fallacious because there is no reason to believe that
one event must inevitably follow from another without an argument for such a
claim. This is especially clear in cases in which there is a significant number
of steps or gradations between one event and another.
1. "We have to stop the tuition increase! The next thing you know,
they'll be charging $40,000 a semester!"
33.
Fallacy: Straw Man
The Straw Man fallacy is
committed when a person simply ignores a person's actual position and
substitutes a distorted, exaggerated or misrepresented version of that
position. This sort of "reasoning" has the following pattern:
1. Person A has position X.
2. Person B presents position Y (which is a distorted version of X).
3. Person B attacks position Y.
4. Therefore X is false/incorrect/flawed.
This sort of
"reasoning" is fallacious because attacking a distorted version of a
position simply does not constitute an attack on the position itself. One might
as well expect an attack on a poor drawing of a person to hurt the person.
1. Prof. Jones: "The university just cut our yearly budget by
$10,000."
Prof. Smith: "What are we going to do?"
Prof. Brown: "I think we should eliminate one of the teaching assistant
positions. That would take care of it."
Prof. Jones: "We could reduce our scheduled raises instead."
Prof. Brown: " I can't understand why you want to bleed us dry like that,
Jones."